code: def test_undo_start_stop(self):
      # test the undo_block_start and undo_block_stop methods
      text = self.text
  
      text.insert("insert", "foo")
      self.delegator.undo_block_start()
      text.insert("insert", "bar")
      text.insert("insert", "bar")
      self.delegator.undo_block_stop()
      self.assertEqual(text.get("1.0", "1.3"), "foo")
  
      # test another code path
      self.delegator.undo_block_start()
      text.insert("insert", "bar")
      self.delegator.undo_block_stop()
      self.assertEqual(text.get("1.0", "1.3"), "foo")
  
file_path: cpython/Lib/idlelib/idle_test/test_undo.py
imports: from idlelib.undo import UndoDelegator
  import unittest
  from test.support import requires
  from unittest.mock import Mock
  from tkinter import Text, Tk
  from idlelib.percolator import Percolator
label_desc: Use image node_id 9 for calling the UndoDelegatorTest obj's underlying member method code with example usage: obj.test_undo_start_stop() without return types